One of the most important requirements in the training of military personnel, especially in those branches of the service wherein there is a need to train in the area of projectiles e.g. bombs, shells etc., is the ability to detect the accuracy of the subject being trained. In the air force, for example, it is important to be able to determine the accuracy of bombing etc. in order to calibrate equipment and train pilots and bombardiers.
Presently there is being used various devices for determining the exact area in which a projectile falls. The most used devices are pyrotechnics which produce a flash of light and a puff of smoke to indicate the site of projectile impact. One such device employs titanium tetrachloride which produces a cloud of smoke when it reacts with the moisture in the air on impact. A second such device is a red phosphorus bearing projectile which emits a flash of light upon impact.
The problems attendant these types of detection devices are numerous. The main problems, however, are that the phosphorus device generates light by burning and, as a result, many items with which the burning phosphorus comes into contact also burn i.e. trees, shrubs; grass etc. while the titanium tetrachloride devices, because they only emit smoke, are practically useful for nighttime detection.
Amine materials known to emit chemiluminescent light on contact with the atmosphere have also been used however, the light emitted is not of a high enough intensity to provide accurate detection.